The present invention relates generally to pumps and pertains particularly to an improved continuous surface frictional drag pump.
Rotary disc pumps having smooth surfaces that impose an impelling force on a fluid by means of frictional or boundary layer drag on the fluid were initially proposed by Nicholas Tesla around 1913. Such pumps, however, have been of very little interest, however, due to the lack of efficiency as compared to traditional bladed impeller pumps.
Such pumps which operate on the principle of boundary layer drag have been of interest and proposed for use with certain specific fluids such as human blood. Such application, however, requires low pressure and low force on the fluid.
Pumps operating on this principle, however, are of interest in other applications due to the lack of impediment to the passage of solid particles through the pump. The problem of sufficiently high pressures and efficiencies have, however, continue to be a problem.
It is therefore desirable that an improved continuous blade multi-stage pump be available.